Rendered image is way too pixelated
The Resolution $X$ and $Y$ settings for the Render Dimensions determine the render size in pixels.
But when you use percentage control, the number of pixels will be reduced if you use a smaller number than 100%.
In this example, a 1920 x 1080 image is rendered at 1%, yielding an image measuring of only 19 x 10 pixels.
Hardly enough pixels to make the sense of the original scene.